There are a variety of applications where a flexible, gas permeable material which is also hydrophobic and oleophobic is useful. For example, in the clean up of chemical waste sites, a prevalent problem in our country today, there is a need for protective clothing which (1) will resist passage of both oil and water-based compositions and (2) is gas permeable, allowing passage of air and water vapor, thereby permitting transmission of air and moisture (perspiration) through the material from the body side to the atmosphere. In this type of application, detergent and solvent resistant characteristics are also valuable since the nature of the compositions encountered is not always known. Similarly, the need for protective clothing and shelter for military personnel who, in the field, may be exposed to deleterious oil and water-based aerosols by virtue of field conditions, provides additional incentive for the development of light-weight, flexible or pliant, microporous (thereby being gas permeable) hydrophobic, oleophobic structures which can be tailored to form protective fabric used to form field shelters, e.g., tents, and used in vehicle protection and the like.
The subject invention is directed to composite structures which provide the desired properties in such applications.